Union Registry maritime accounts (MOHA)

Background: from per-Member-State registries to the Union Registry

The EU Emissions Trading System established by Directive 2003/87/EC launched in 2005 with a federated registry architecture. Each Member State operated its own national registry, and a Community Independent Transaction Log reconciled cross-registry transfers. The model proved fragile. Cyber-intrusions and VAT-carousel frauds in 2010 and 2011, including the BlueNext theft of around 475,000 allowances from the Czech registry and the Romanian phishing loss of around 1.6 million allowances from a cement-sector account, exposed the per-Member-State user-interface as the weakest link.

The Commission’s response was structural consolidation. From 1 January 2012 for aviation and from 1 January 2013 for the start of phase 3, all national registries migrated into a single Commission-operated platform: the Union Registry. The legacy per-Member-State databases were decommissioned. National administrators (typically climate-ministry agencies) retained authority over account opening, KYC review, and account suspension within their jurisdiction, but the database, user interface, back-end servers, and reconciliation log are all operated by the Commission’s DG CLIMA in cooperation with DG DIGIT.

The transaction log was rebuilt in parallel. The Community Independent Transaction Log was replaced by the EU Transaction Log (EUTL), which screens every proposed transaction in real time against a rule set: account-status checks, balance checks, cooling-off periods, four-eyes-principle compliance, blacklist screening, and integrity hashing. A failed rule rejects the transaction before it lands; a passing transaction is timestamped and recorded immutably.

When the maritime sector was added by Directive (EU) 2023/959, the registry architecture was extended to host shipping companies. The Commission amended the Registry Regulation in 2023 to introduce the MOHA class alongside existing operator and aviation-operator holding accounts, and to slot the new class into the same EUTL screening, the same 26-hour anti-fraud delay, the same four-eyes governance, and the same cybersecurity envelope already applied to fixed-installation operators. A shipping company surrendering an EUA in 2026 uses the same database row format as a steel mill that surrendered its first EUA in 2005.

Account types in the Union Registry

The Union Registry distinguishes accounts by purpose and by the rights they confer on the holder. Six classes are relevant to the maritime conversation.

The Operator Holding Account (OHA) is the legacy account class for stationary installations covered by Annex I of the directive. A power station, a steel mill, a cement kiln, a refinery, or a chemical plant holds one OHA per permitted installation. Free allocation is delivered to the OHA every February; surrender is executed from the OHA every April.

The Aircraft Operator Holding Account (AOHA) was introduced in 2012 when aviation joined the system. Each commercial aircraft operator holds one AOHA, used for free allocation receipt (where applicable), auction-purchase deposit, and surrender. The AOHA was the structural template for the maritime equivalent.

The Maritime Operator Holding Account (MOHA) is the new account class created by Commission Delegated Regulation (EU) 2023/2904 for shipping companies under Article 3gd. The MOHA mirrors the AOHA functionally: it receives auction-purchased EUAs, it receives any allocation (zero in the maritime case for the foreseeable future), it executes surrender, and it can transfer to and from a Trading Account.

The Trading Account (TA) is open to any legal or natural person who passes KYC. Banks, hedge funds, commodity trading houses, brokers, and shipping companies that want to manage market exposure separately from their compliance balance hold one or more Trading Accounts. The maritime relevance is that a shipping company can choose to keep its MOHA at minimum balance (just enough to cover the next surrender) and warehouse its strategic position in a Trading Account, transferring only what it needs for the 30 September deadline.

The Person Holding Account (PHA) is the residual class for individuals, NGOs, academic institutions, and other legal persons who want to hold allowances without operator status. The PHA was once important for the offset market; today it is rare in the maritime context but exists in the taxonomy.

The Verifier Account (VA) is held by accredited verifiers under Regulation (EU) 2018/2067. The VA does not hold allowances. It exists to grant the verifier read-and-attest rights over its clients’ emissions reports inside the registry user interface, allowing the verifier to electronically sign the verification statement that flows from THETIS-MRV into the surrender workflow.

Two further structural accounts complete the architecture. The EU Allocation Account is the sole source from which new EUAs enter circulation, operated by the Commission. The EU Surrender Account is the sole destination for surrendered EUAs, after which the Commission cancels them. Both are administrative in nature and not held by any market participant.

Maritime Operator Holding Account (MOHA): the new class for shipping

The MOHA was added to the registry account taxonomy by Article 1 of Commission Delegated Regulation (EU) 2023/2904, which inserted a new Article 16a into the Registry Regulation 2019/1122. The amendment defines the MOHA as the dedicated holding account for shipping companies as defined in Article 3gd of Directive 2003/87/EC, and specifies that one MOHA is opened per shipping company in the registry of its administering authority.

Three operational rules distinguish the MOHA from the legacy OHA. First, the MOHA is bound to a legal-entity identifier (the shipping company under Article 3gd) rather than to a permitted installation. The MOHA does not list specific vessels. The vessels attributed to the company are tracked separately in THETIS-MRV; the registry only holds the aggregate compliance position.

Second, the MOHA has zero allocation as a default. Free allocation entries appear on the MOHA only if the directive grants such an allocation, which at present applies to ice-class voyages and to specific outermost-region exemptions and is administered through the verified-emissions reduction in THETIS-MRV rather than through a registry deposit. The practical implication is that a MOHA opens with a balance of zero and is funded entirely by inbound transfers from auction-purchase intermediaries or from a Trading Account.

Third, the MOHA is the only account from which a shipping company can execute a maritime surrender. A Trading Account, even one held by the same legal entity, cannot deliver to the EU Surrender Account on a maritime compliance flow. The transfer must move first from the Trading Account to the MOHA, then from the MOHA to the Surrender Account. This two-hop rule preserves the audit trail: every surrendered EUA has demonstrably passed through the supervised compliance account before cancellation.

The MOHA carries a unique account identifier in the EUTL of the form EU-100-NNNNNNN-N-NN, where the third block identifies the Member State of the administering authority and the fourth and fifth blocks form a sequence number and check digit. The identifier is durable: it survives company-name changes and persists through M&A succession events.

MOHA opening procedure

Opening a MOHA is a multi-step process that runs in parallel with the Article 3gf attribution of the company to its administering authority. The procedure is set out in Articles 14 to 19 of Regulation (EU) 2019/1122, as amended for maritime by 2023/2904.

Step 1: application. The shipping company files with the registry desk of the administering authority identified under Article 3gf. For German-attributed companies the desk is DEHSt; for Greek the Ministry of Environment and Energy; for Cypriot, Maltese, and Danish the relevant climate-ministry teams. The form requires legal name, registered address, LEI, VAT registration where applicable, directors and senior managers, two designated authorised representatives, and the IMO-issued company-identification number used in THETIS-MRV.

Step 2: identity verification of directors and representatives. Each named individual submits certified passport or government-ID copies, proof of address within three months, and a criminal-record extract. Articles 16 and 17 of 2019/1122 require refusal if any director was convicted in the preceding five years of fraud, money laundering, terrorist financing, or any financial-markets offence; the standard mirrors bank-account opening under Directive (EU) 2015/849.

Step 3: bank-account verification. The applicant nominates a bank account in its own name at an EEA, Swiss, or AML-equivalent credit institution. The registry runs a small notional credit transfer; the applicant reports back the exact cents value to confirm control.

Step 4: KYC/AML file build. The national administrator runs the company, directors, and representatives against EU and UN sanctions lists, against the Commission’s high-risk-third-country list under 2015/849, and against its own watch lists. Hits trigger enhanced due diligence: source-of-funds documentation, beneficial-ownership disclosure down to the 25 percent threshold, and sometimes on-site visits.

Step 5: company-vessel attribution cross-check. The desk pulls the THETIS-MRV record, verifies at least one vessel attributed under Article 3gd, and confirms the IMO company-identification number matches. Mismatches (the most common application defect) usually trace to stale IMO records after a management transfer.

When all five steps clear, the administrator authorises account creation; the MOHA is provisioned in the EUTL within five working days and representatives receive credentials by separate registered post. The full opening process takes four weeks (clean German or Cypriot application from a well-known liner operator) to six months (opaque single-ship company in a Caribbean structure with new directors). The directive does not recognise account-opening delay as an excuse for missing the 30 September y+1 surrender deadline, so the operational rule is to apply at the earliest moment, ideally during the first MRV reporting year.

Trustee model for non-EU shipping companies

A large share of world tonnage is operated by companies registered outside the EU: Singapore, Hong Kong, the United Arab Emirates, the British Crown Dependencies, the United States, Norway, the United Kingdom, China, Japan, and South Korea between them account for the majority of beneficial vessel ownership. Many of those companies have no legal presence in any Member State. The directive nevertheless attributes them to an administering authority based on port-call density under Article 3gf, and Regulation 2019/1122 requires them to hold a MOHA in that administering authority’s registry.

To bridge the gap, Commission Delegated Regulation (EU) 2023/2904 introduced the EU-incorporated authorised representative model for non-EU shipping companies. The rule is that a shipping company without an EU registered office must appoint an EU-incorporated legal entity as its authorised representative to receive procedural communications, to host the registry-account-administrator function, and in many implementations to be the legal counterparty for the MOHA itself.

The structural pattern is the trustee model. The non-EU shipping company contracts with an EU-incorporated trustee (frequently the EU subsidiary of a maritime law firm or a specialised compliance-services provider) which opens the MOHA in the trustee’s name on behalf of the principal. The trust deed specifies that allowances are held for the beneficial benefit of the non-EU principal, that the trustee’s role is purely fiduciary, and that the trustee executes the principal’s instructions on transfers and surrenders. The trustee does not assume the directive’s compliance liability, which remains with the shipping company under Article 3gd.

Member States vary in implementation. Germany under DEHSt prefers a direct MOHA in the non-EU company’s name with an EU authorised representative as service-of-process agent. Greece accepts both direct and trustee models and has streamlined the trustee path through licensed providers. Cyprus, Malta, and Denmark are pragmatic about the trustee model given their share of internationally beneficially owned tonnage. The choice is governed by national administrative law and by whether the non-EU company can satisfy the KYC desk directly.

The trustee model carries three operational risks. Counterparty risk: trustee insolvency may freeze the MOHA pending administrator review even though allowances are held on trust; mitigate via bankruptcy-remote structuring and segregated client assets. Execution risk: principal instructions must be acted on within a tight surrender window; mitigate via SLA with hard cutoffs and an escalation chain. Regulatory risk: a future amendment could narrow the trustee model; mitigate via legal monitoring and contractual flexibility to migrate to a direct MOHA.

Transaction types: allocation, transfer, surrender, security

The MOHA supports four functional transaction types, each with distinct EUTL screening rules.

Allocation receipt is the inbound deposit of EUAs from the EU Allocation Account or from an auction-clearing flow. Auction allocations route through the EEX primary auction, which clears in the auction-clearing-house’s TRA (Trading Registry Account) and is transferred from there to the bidder’s nominated account. For a shipping company that bids directly at EEX, the EUAs land in the company’s MOHA. For a shipping company that bids through a broker, the EUAs land in the broker’s Trading Account first and then are transferred to the MOHA on a downstream instruction. Allocation receipt is screened by the EUTL for source-account legitimacy, target-account-open status, and quantity sanity, and is not subject to the 26-hour delay because the source is itself a registry account already supervised by the Commission.

Transfer to or from a Trading Account is the most frequent transaction type for an active shipping company. The transfer can be intra-entity (the company’s own Trading Account funded for treasury reasons) or inter-entity (a transfer from a counterparty’s Trading Account on a bilateral OTC trade). EUTL screening checks source balance, target-account status, four-eyes principle (where the transfer exceeds the four-eyes threshold), and the 26-hour delay clock if the transfer is outbound from the MOHA.

Surrender to the EU Surrender Account is the compliance-closing transaction. A shipping company logs in to its national-administrator registry user interface, enters the surrender amount equal to its verified emissions liability scaled by the phase-in factor, confirms the surrender via the four-eyes flow, and the EUTL routes the EUAs to the Commission’s Surrender Account where they are cancelled. The surrender transaction is not subject to the 26-hour delay because the destination is a Commission-controlled cancellation account, not a third-party recipient.

Transfer to a Security Account is the encumbrance flow used when allowances are pledged as collateral for a financing facility. A shipping company that has borrowed against its EUA inventory transfers the pledged EUAs to a Security Account held in the lender’s name; on loan repayment the lender returns the EUAs; on default the lender forecloses by retaining or liquidating. The Security Account is a sub-class of the Trading Account that bears a registry flag indicating its collateral function. Security transfers are screened by EUTL for the standard rules and additionally for the security-account-flag check.

A shipping company’s annual MOHA activity log will typically show: zero or one allocation receipt, two to ten transfers from Trading Accounts (the build-up of the surrender pile through the year), one surrender to the EU Surrender Account on or before 30 September, and zero or more security transfers if the company has financed against EUAs.

Four-eyes principle for high-value transactions

Article 23 of Regulation (EU) 2019/1122 requires that every account hold at least two authorised representatives, and that any outbound transaction above a national-administrator-set threshold be authorised by both representatives acting independently. This is the four-eyes principle.

The mechanic is straightforward. Authorised Representative A initiates the transaction in the registry user interface, providing the destination account, the quantity, and any free-text reference. The transaction enters a “pending second approval” state. Authorised Representative B logs in separately, reviews the pending instruction, and either approves or rejects. Approval releases the transaction to the EUTL screening queue; rejection cancels it. If neither approval nor rejection is recorded within a national-administrator-set window (typically 7 days), the transaction expires.

Two implementation details matter. First, the two representatives cannot be the same physical person logged in under different credentials; the registry enforces a separation through user-attribute checks and through IP and device fingerprinting. Second, the threshold above which four-eyes is mandatory is set per Member State within a Commission-mandated band, but for maritime MOHAs the practical position is that effectively all surrender transactions and most outbound transfers exceed the threshold, so four-eyes is the operational norm rather than the exception.

The four-eyes principle is the single most effective fraud control in the registry. The 2010 to 2011 fraud wave that motivated registry consolidation exploited single-signatory accounts where one compromised credential set delivered the attacker the full balance. After the 2013 consolidation and the universal application of four-eyes, the Commission has reported only marginal residual fraud levels. The cost is operational friction: a shipping company must keep both authorised representatives reachable in the surrender window, must rotate them when one leaves the company, and must maintain a backup-representative process for vacation cover.

A practical pattern for shipping companies is to nominate the chief financial officer or treasurer as Authorised Representative 1 and the head of compliance or general counsel as Authorised Representative 2. This separates the financial signing authority from the compliance attestation, gives both individuals ample reason to scrutinise the transaction, and survives most personnel changes through structured handover.

The 26-hour anti-fraud delay on outbound transfers

Article 36 of 2019/1122 imposes a 26-hour delay on outbound transfers from any holding account, including the MOHA, when the destination is not on the account’s “Trusted Account List”. The clock starts when the second four-eyes approval is recorded and ends 26 hours later, at which point the EUTL releases the transfer to the destination account.

The 26-hour figure is calibrated to span at least one full UTC business day. A transaction approved at 16:00 CET on Wednesday is released at 18:00 CET on Thursday. The window allows the account holder, the national administrator, and the Commission’s registry operations team to detect a fraudulent or erroneous transfer and to issue a stop order before the EUAs leave the account.

The Trusted Account List is a per-account whitelist maintained by the account’s authorised representatives. Any account on the list, typically the company’s own Trading Account, the company’s broker’s Trading Account, the EU Surrender Account, and a small number of regular counterparties, is exempt from the 26-hour delay. Adding an account to the Trusted Account List itself triggers a 7-day cooling-off period before the new entry becomes effective, mirroring the SEPA bank-transfer-beneficiary cooling-off pattern.

For maritime surrender, the 26-hour delay is not on the critical path because the EU Surrender Account is by definition trusted. The delay does sit on the path of intra-group treasury transfers between a shipping company’s MOHA and a sister-company Trading Account that has not yet been added to the Trusted Account List. This is the most common operational surprise for newly opened maritime accounts: the first transfer between MOHA and the company’s chosen trading vehicle takes 26 hours, blocking same-day execution of an opportunistic auction purchase.

IT architecture: EUTL transaction log + per-Member-State UI

The Union Registry’s IT stack runs in three layers.

The back-end database is the canonical store of every account, every balance, every transaction, every authorised-representative credential, and every audit log. It is operated by the Commission’s DG CLIMA in collaboration with DG DIGIT, hosted in the Commission’s data centres, and replicated for disaster recovery. No Member State has direct access to the back-end database tables; supervisory access is mediated through the registry user interface and through structured query and reporting tools.

The EU Transaction Log (EUTL) is the rules engine that screens every proposed transaction in real time. The EUTL maintains a hash chain of every settled transaction, which means a transaction once settled cannot be silently altered without breaking the chain. The EUTL is also the integration point with external systems: the EEX auction clearing flow, the Commission’s allocation-issuance flow, the cancellation flow on the Surrender Account.

The per-Member-State registry user interface is the front-end through which authorised representatives, national administrators, and verifiers interact with the system. Each Member State operates a localised portal in its national language with its own branding, but the underlying database and the EUTL screening are common across all portals. A German MOHA holder logs in through the DEHSt portal, sees the user interface in German, and interacts with the back-end through the DEHSt’s authentication layer; a Greek MOHA holder logs in through the Greek portal in Greek; the data and rules underneath are identical.

The integration with THETIS-MRV is bidirectional. THETIS-MRV is operated by EMSA and holds the verified emissions data per company per year. When a verifier signs a verification statement in THETIS-MRV, the value flows through to the Union Registry as the surrender obligation that the MOHA must meet by 30 September y+1. The flow is automated for the headline number; the supporting documentation remains in THETIS-MRV and is accessed through cross-system links.

The cybersecurity envelope of the registry is documented in the Commission’s Registry Functional Specifications and the technical annexes to 2019/1122. It includes mandatory two-factor authentication for every authorised representative, IP-range whitelisting at national-administrator request, hardware-token options for enhanced security, audit logging with tamper-evident storage, intrusion detection at the application layer, and periodic third-party security assessments commissioned by DG DIGIT.

Integration with THETIS-MRV

THETIS-MRV is the European Maritime Safety Agency’s reporting platform for the MRV Regulation 2015/757. It captures, per shipping company per calendar year, the emissions monitoring plan, the per-vessel reported data, and the verifier’s verification statement. THETIS-MRV is the source of truth for emissions; the Union Registry is the source of truth for allowances. The two systems must reconcile for the surrender obligation to be valid.

The reconciliation works as follows. By 31 March of year y+1 the shipping company submits its annual emissions report to its verifier through THETIS-MRV. The verifier audits the report and signs a verification statement by 30 April. The verified emissions value, scaled by the phase-in factor and by any directive-specified exemption (ice-class voyage adjustment, outermost-region adjustment), produces the surrender liability. THETIS-MRV publishes the verified emissions and the derived surrender liability into the company’s Union Registry account record. The MOHA’s user interface displays the figure as the “outstanding surrender obligation” line item, against which the authorised representative initiates the surrender transaction.

Two reconciliation points to watch. First, the verifier must hold a Verifier Account in the registry of the administering authority for the cross-system signature to flow. If the verifier has been accredited in another jurisdiction, the verifier opens a Verifier Account specifically in the administering Member State’s registry. Second, any post-publication correction to the verified emissions (for example a verifier-issued addendum after a clerical-error discovery) updates the THETIS-MRV record, but the Union Registry surrender-obligation line is recalculated only on a manual trigger from the national administrator. The shipping company must therefore confirm with both systems that the figure used for the actual surrender matches the latest verified value.

Account closure procedures

A MOHA is closed in three scenarios: voluntary closure by the holder, administrative closure by the national administrator, or automatic closure following a definitive cessation of the shipping company.

Voluntary closure is initiated by the authorised representatives. The holder transfers any remaining EUA balance out of the MOHA, settles any outstanding surrender obligations, files a closure request with the national administrator, and waits for the administrator to process the request. Article 30 of 2019/1122 sets a 60-day window during which the national administrator can decline the closure if there is an unresolved compliance issue. After the 60 days, the closure is effective; the MOHA is flagged “closed” in the EUTL and can no longer receive or send transactions.

Administrative closure is initiated by the national administrator under Article 32 if the holder has been struck off the THETIS-MRV company register (no attributed vessels for an extended period), or has had its directors convicted of fraud or money-laundering offences, or has refused to update its KYC file when required. Administrative closure is preceded by a notice and a 30-day cure window. If the holder remedies the defect within the window, the closure is rescinded; if not, the MOHA is frozen, any remaining balance is transferred to the EU Allocation Account for redistribution under separate procedures, and the account is flagged “closed”.

Automatic closure triggers on definitive cessation of the shipping company under national insolvency law. The national administrator receives a court certificate of insolvency, validates that no successor entity has assumed the directive’s compliance liability, and closes the MOHA. Any unsurrendered emissions liability survives the closure and is pursued against the directors personally or against any successor entity identified through M&A succession rules.

A closed MOHA is not deleted from the database. Its transaction history is retained for at least 15 years under Article 73 of 2019/1122, both for audit purposes and because a closed-and-reopened pattern is a known fraud signal that the EUTL screens against.

Succession: M&A, fleet transfer, change-of-flag

Shipping is a sector with frequent corporate restructuring: liner-trade consolidations, distressed-asset sales, fleet transfers between sister companies, change-of-flag events, and management-takeover transactions. Each of these can affect the identity of the shipping company under Article 3gd and therefore the identity of the MOHA holder.

The directive treats the shipping-company identity as a function of the Document of Compliance (DoC) holder under the ISM Code. If the DoC holder changes, the shipping company changes, and the MOHA may need to follow.

For an acquisition (Company B buys Company A): if Company A is dissolved and its vessels migrate to Company B’s DoC, Company A’s MOHA is closed (balance transferred to Company B’s MOHA) and Company A’s surrender obligations through the transfer date pass to Company B as universal successor. If Company A survives as a subsidiary with its own DoC, Company A’s MOHA continues unchanged.

For a fleet transfer between sister companies under common ownership, the new DoC holder triggers a new MOHA; the transferring entity holds the surrender obligation for emissions accrued before transfer, the receiving entity from transfer onward.

For a change-of-flag with no change of DoC holder, there is no MOHA impact. The shipping company under Article 3gd is the operational responsibility holder, not the registry of the vessel.

For a management takeover (Owner A switches manager from X to Y for the same vessels), the DoC moves from X to Y on the affected vessels. If those vessels are X’s only attributed fleet, X’s MOHA is wound down; otherwise X retains the MOHA for its remaining fleet, and Y opens a MOHA if it does not already hold one.

The procedural mechanism is a coordinated Article 32 administrative action on receipt of M&A agreement, new DoC, updated THETIS-MRV attribution, and company-law succession evidence. Clean cases run six to ten weeks; complex cross-border or contested cases take much longer.

Dispute and reversal mechanism for fraudulent transactions

Article 70 of 2019/1122 establishes the dispute and reversal mechanism for transactions affected by fraud, error, or malfeasance. The mechanism is layered to balance two competing concerns: the need to remedy theft and the need to protect bona-fide downstream holders who acquired allowances in good faith on the secondary market.

Pre-settlement reversal is the first layer. During the 26-hour anti-fraud delay the source-account holder can request the national administrator to reverse a pending transfer if the source account has been compromised. The administrator validates within hours and instructs the EUTL to cancel; the EUAs never leave the source account. This is the cleanest remedy and works only if fraud is detected within the 26-hour window.

Post-settlement reversal against a non-bona-fide recipient is the second layer. If the recipient is identifiably complicit (proceeds traceable to a sanctioned wallet, recipient on a fraud watchlist, recipient is the criminal actor), the national administrator can apply to the Commission for a forced reversal that debits the recipient and credits the source account.

Post-settlement non-reversibility against a bona-fide holder is the third layer. EU law protects a bona-fide acquirer of a financial-market instrument against retrospective dispossession; allowances acquired in good faith by a downstream holder cannot be clawed back. The defrauded original holder’s remedy is a civil action against the criminal actor, supported by the registry’s transaction history. EU national-court rulings on the 2010 to 2011 fraud wave consistently held bona-fide holders unimpeachable.

For maritime operators the implication is to invest in pre-settlement detection. The 26-hour delay, four-eyes principle, Trusted Account List, and EUTL alerting are the layers that catch fraud before the bona-fide-holder line. Once it crosses that line the loss is realised, and recoverable value typically falls far short of EUA face value.

Cybersecurity requirements

Regulation (EU) 2019/1122 and its technical annexes impose layered cybersecurity requirements on the registry’s operators and on the account holders.

On the operator side, the Commission’s data centres run mandatory two-factor authentication, hardware-token credentials for high-risk accounts, IP-range whitelisting on request, tamper-evident audit logs with cryptographic hashing, intrusion detection at the application layer, periodic third-party penetration testing, and tested geographic-replication failover.

On the account-holder side, Article 25 obligations flow to the shipping company: use secure dedicated devices for registry access, store credentials per industry-standard secret-management practice, report any suspected compromise to the national administrator within 24 hours, rotate representative credentials on personnel changes within 5 working days, and maintain a documented internal transactions procedure.

Two common maritime failures recur. Credential sharing: a small or medium operator under operational pressure lets an assistant log in using the CFO’s credentials. The audit log records every login by IP and device fingerprint, and a deviation triggers EUTL alerting; the remedy is procedural enforcement of personal logins. Unrotated credentials after departure: a treasurer who leaves in March must have credentials revoked the same day, or the residual access becomes a vector for both deliberate misuse and inadvertent inclusion in the leaver’s archive. The cure is a checklist tied to the offboarding workflow.

Member-State competent authority mappings

Each EU and EEA Member State designates a national administrator that operates the registry portal for accounts attributed to that Member State. The mapping for shipping is a function of the Article 3gf attribution, not of the company’s registered office.

Germany’s national administrator is the Deutsche Emissionshandelsstelle (DEHSt), hosted within the Umweltbundesamt under the Federal Ministry for Economic Affairs and Climate Action, with a substantial maritime sub-team that handles the share of internationally beneficially owned tonnage attributed to Germany. The German registry portal is in German with English supplementary documentation.

Greece’s national administrator is the Ministry of Environment and Energy, climate-change directorate, which hosts a large maritime portfolio reflecting Greek-owned tonnage operating into EU ports.

Cyprus’s national administrator is the Department of Environment of the Ministry of Agriculture, Rural Development and Environment, with a streamlined process for trustee-model MOHAs.

Malta’s national administrator is the Energy and Water Agency, similarly oriented to international tonnage.

Denmark’s national administrator is the Danish Energy Agency, with a mature shipping-sector practice given the Danish liner-trade history.

The Netherlands operates through the Nederlandse Emissieautoriteit (NEa), France through the Caisse des Dépôts et Consignations acting on behalf of the climate ministry, Italy through the Comitato nazionale per la gestione della Direttiva 2003/87/CE in the environment ministry, Spain through the Ministry for the Ecological Transition and the Demographic Challenge climate-change office, and Portugal through the Agência Portuguesa do Ambiente.

The full list of competent authorities is published by the Commission and updated periodically as Member State machinery-of-government changes occur. The shipping company should consult the authoritative list at the moment of MOHA application; the substantive procedure is harmonised by Regulation 2019/1122 even where the administrative organ differs.

For non-EEA flags and for trustee-model accounts, the competent authority remains the Article 3gf-attributed Member State; the trustee’s own residence is irrelevant for authority purposes but does set the practical service-of-process address.

Cross-border surrender flow

A maritime voyage’s first or last EU port frequently lies in a Member State other than the one whose national administrator hosts the shipping company’s MOHA. A Greek-attributed shipping company’s vessel may load at Antwerp, discharge at Hamburg, and bunker at Rotterdam, generating emissions in the territorial reach of Belgium, Germany, and the Netherlands respectively. The MOHA is in Greece; the emissions accrued under the maritime scope rules on those voyages.

The surrender flow under the directive does not split along port-state lines. The full verified emissions liability, aggregated across all attributed vessels and all in-scope voyages, sits on the Greek-attributed company’s Greek MOHA, and the entire surrender flows to the single EU Surrender Account through that MOHA. There is no per-port-state surrender, no per-flag-state surrender, and no per-voyage allocation between Member States. The Article 3gf attribution is the single point of registry-level accountability.

What is cross-border is the revenue distribution at the auction-revenue level. EUA auction revenues are distributed to Member States under a formula that includes a maritime-specific allocation key tied to verified emissions attributable to each Member State’s port-call share. The mechanic is administered by the Commission and EEX; it does not involve the MOHA and does not change the surrender flow.

For the shipping company, the practical implication is that even if the operational fleet calls at twenty Member State ports across a year, the registry interaction is single-administrator. The administering authority handles the company’s MOHA, KYC, four-eyes authorised-representative governance, surrender execution, and any compliance dispute. The shipping company does not need to maintain registry presence in any other Member State.

What does flow across borders is the compliance-data picture. THETIS-MRV holds the per-vessel per-voyage emissions data, accessible by national administrators across the EU subject to the regulation’s data-sharing provisions. Port-state-control authorities in any Member State can query the company’s surrender status during a port-state inspection; non-surrender for two reporting periods triggers the Article 16(11a) port-state-denial pathway, executable at any Member State port regardless of the MOHA’s location.

Formula, assumptions, and limits

Formula

The MOHA balance at any moment in time follows simple inventory accounting:

where $N_{\text{allocated}}$ is the cumulative free-allocation deposits (zero in practice for maritime), $N_{\text{purchased}}$ is the cumulative inbound transfers from auction-clearing intermediaries and Trading Accounts, $N_{\text{surrendered}}$ is the cumulative outbound transfers to the EU Surrender Account, and $N_{\text{sold}}$ is the cumulative outbound transfers to other holding or Trading Accounts.

Derivation

The formula is an inventory equation with no time discounting because EUAs are not consumed or depreciated in the registry. Each EUA on the MOHA is fungible and bears no maturity, so the balance is the simple algebraic sum of inflows minus outflows since the MOHA was opened. The EUTL implements this exact equation at every transaction, validating that $N_{\text{EUA,balance}} \geq 0$ at all times by rejecting any transaction that would breach the floor.

Assumptions

The inventory equation assumes no loss outside the four enumerated flows. This holds for an account that is not subject to fraud, dispute reversal, or administrative confiscation. It assumes that the surrender liability for year y is satisfied entirely from the MOHA, which is required by the two-hop rule (Trading Accounts cannot deliver surrender directly). It assumes that the four flows are recorded at face value, which is true under the EUTL’s hash-chained ledger.

Worked example

A Greek-attributed shipping company operates a 50,000 dwt bulk carrier with a verified annual emissions liability of 24,000 tCO2e for calendar 2025 (after the 70 percent phase-in factor). Across 2025 the company purchases 24,000 EUAs through its broker, of which 20,000 transit directly into the MOHA from the broker’s Trading Account in monthly tranches, and 4,000 land in the company’s own Trading Account first and then move to the MOHA in August. The MOHA opening balance was zero. The surrender on 30 September 2026 is 24,000 EUAs to the EU Surrender Account. The closing MOHA balance is 0 + 24,000 - 24,000 - 0 = 0. The same company under-buys by 1,000 EUAs (purchases 23,000 only), surrenders 23,000, and sits on a 1,000 EUA shortfall: in this case the surrender is incomplete, Article 16(11) penalty engages, and the directive’s restitution mechanism requires the missing 1,000 EUAs to be acquired and surrendered in a subsequent cycle on top of paying the EUR 100 per tonne penalty.

Edge cases and limits

The inventory equation does not capture timing risk between an emissions year and the surrender year. Emissions accrue continuously through year y; the surrender deadline is 30 September of year y+1. A company that builds its MOHA balance only in August of y+1 carries spot-price risk on every EUA still to be acquired. A company that pre-purchases in y carries futures-curve and counterparty risk. The choice of acquisition timing is not a registry question; it is a treasury question.

The equation also does not address the quality of the EUAs. All EUAs in the registry are fungible by construction, so a 2024-vintage EUA and a 2026-vintage EUA are operationally identical for surrender. Allowances issued under the earlier Kyoto-era CER and ERU tracks are distinct units and cannot be surrendered under the post-2021 EU ETS regime.

Account suspension under Article 32 freezes the balance: $N_{\text{purchased}}$ and $N_{\text{sold}}$ are forced to zero for the suspension duration. A company that has its MOHA suspended in mid-year cannot transfer in or out until the suspension is lifted, and cannot meet the surrender deadline if the suspension extends past 30 September.

Regulatory basis

The inventory accounting is implicit in Regulation (EU) 2019/1122 Articles 36 to 50 (transactions), Articles 56 to 60 (surrender), and Article 73 (transaction history retention). The maritime-specific overlay sits in Commission Delegated Regulation (EU) 2023/2904 which adds the MOHA, the EU-incorporated authorised representative, and the cross-border-surrender flow.

Common errors

The most common error is treating the MOHA balance as the company’s net carbon position. It is not: it is the registry inventory, which excludes any forward-contract position held at EEX or ICE and excludes any pooled-position commitment under FuelEU compliance balance pooling. A company can show a zero MOHA balance and still hold a substantial economic carbon hedge through forward EUA futures or a pool position.

The second common error is forgetting the two-hop rule and attempting to surrender directly from a Trading Account. The transaction is rejected by EUTL screening; the company must first transfer to the MOHA and then surrender, which adds the 26-hour-delay window if the Trading Account is not on the Trusted Account List. Surrender-window time pressure means this rule must be drilled into the operational team and tested in advance of the September surrender deadline.

The third common error is misalignment between the Article 3gd shipping-company identity and the MOHA holder. If the company operating the vessel under the ISM Code is Manager Y but the MOHA was opened in the name of registered owner X, the surrender is from the wrong account. The fix is administrative and slow, and it is not infrequent in fleets that have been re-managed since the MOHA opened.

See also

• /wiki/eu-ets-for-shipping
• /wiki/eu-ets-maritime-scope-phase-in
• /wiki/eu-ets-allowance-allocation-shipping
• /wiki/eu-ets-surrender-mechanics-shipping
• /wiki/fueleu-compliance-balance-pooling
• /wiki/marine-gfs-methodology
• /wiki/imo-dcs-vs-eu-mrv
• /wiki/imo-net-zero-framework
• /calculators/eu-ets-eua-liability
• /calculators/eu-ets-scope
• /calculators/eu-ets-phase-in
• /calculators/eu-ets-pool-surrender
• /calculators/fueleu-compliance-balance